Recently, by a spread of DTP (Desk Top Publishing), a process in which an image inputted from a scanner is image-edited and paginated on the software of the computer, is generalized and the editing in the full-digital does not also become rare.
In such a process, in order to promote the more efficiency, an image setter output by which the image data whose page-edition is completed is directly outputted to the film, or CTP (Computer to Plate) output which directly conducts the image recording onto the printing plate, furthermore, CTC (Computer to Cylinder) by which the image recording is directly conducted onto the printing plate wound on a cylinder of printer, are conducted.
Further, in a process of proofing in such a print process, a proof is made and used for mainly 3 uses of (1) confirmation of mistake inside the working site, that is, first proof, (2) an outer proofing submitted for finishing confirmation for an order person, designer, (3) a print sample submitted as a sample of final print to the machine length of printer.
As described above, in the case where a color print is made, when the color proofing is conducted in a step of original film, the proofing print (color proof) is made by suing each color resolution dot original film which is resolved into Y (yellow) plate, M (magenta) plate, C (cyan) plate, and BK (black)plate, and before the print plate is made, it is inspected whether the layout of the original film is correct, whether color is correct, or whether letters are correct, and the finishing of the print is previously confirmed.
In this case, a film output or print output is once conducted only for proofing confirmation, and there is a problem that uselessness of the film, print plate, or additional operation increases, when the print proofing, or the proofing by the other proofing material is conducted.
Accordingly, particularly, in the process in which the full-digital image formation, editing by such a computer, are conducted, a system by which the color image is directly outputted, which is called DDCP (Direct Digital Color Proof) or DCP (Digital Color Proof) is required.
Such a DDCP is a proof by which, before the color image is recorded on the film for printing by an image setter from the digital image data processed on the computer, or a final print operation which directly makes the print plate by CTP, is conducted, or the image recording is directly conducted on the print plate wound on the cylinder of printer by CTC, the color proof by which the output object which is shown by the digital image processed on the computer is reproduced is made, and the confirmation of its image, color tone, sentence letter is conducted.
Further, as a method for making the color proof, there is a color proof making apparatus by which, when, based on the dot image data of each color separation dot original, a light spot formed of a combination of a plurality of light such as, for example, R, G, B, whose wavelengths are different, is exposed in the silver halide photosensitive material and each dot of 3 fundamental colors Y, M, C, is color-generated, the dot image is reproduced, and the color poof is made. Further, in the apparatus, there is DDCP which is a type by which the color adjustment is conducted, when the primary color (ink mono-chrome) which is the color of the printed part of dot image composing the dot image obtained when each color plate of a plurality of ink is printed and superimposed by the printer, the single colors and overprinted colors (the color in which a plurality of ink are superimposed) and the ground color of the print sheet are adjusted to the object colors adjusting the output intensity of 3 fundamental colors so that respective colors are reproduced (for example, Japanese Patent Application O.P.I. No. 2003-149796).
Hereupon, when the color proof is outputted based on the dot image data in the above-described DDCP, although the color tone is adjusted in the solid area, there is some times a case where a phenomena that the color tone is slightly shifted in the intermediate tone area, is generated. For example, in the cyan part, when the dot % of the dot composing the intermediate tone area is reduced, there is a case where it is watched as if yellow lies.
As this countermeasure, it is considered that a method which is called so called Color Management System (CMS) by which the color adjustment is conducted by using the device link profile obtained from respective device profile showing characteristics of the output color of DDCP and the printing press so that the color tone of the outputted image is adjusted, is used. However, in the color adjustment using the Color Management System, for example, in the print, there is a case where a dot of the color which does not originally exist is mixed, and a problem that the plate inspection property is damaged, is generated. Further, because the color management system can not be used for the image data (dot image data) in which screening for making dots is completed, when outputted based on the dot image data, there is also a problem that the color of the dot image can not be adjusted.
Accordingly, the present applicant proposes a method (for example, Japanese Patent Application O.P.I. No. 2005-86229) by which the color of the printed part of dot image composing the dot image outputted based on the dot image data in DDCP, is composed of the pixel of the output color which is adjusted to an object outputted from the printer, and the pixel of the color whose color tone is different from the object color, and outputted. Hereby, the color adjustment can be conducted in the intermediate tone area, further, by this method, the color adjustment can be conducted even for a case where the dot image is outputted based on the dot image data.